Fountain pen



D- F. MOHNS May 2l; 1946.

FOUNTAIN PEN Filed ont. 12, 1944 l INVENTOR Z/QPNOLM lfinest extremeoperating conditions ceed that amount which:

PatentedMay 2119f016` David F. Molins,

Parker Pen Company, anesville, Wis., a corpol ration of WisconsinApplication octtber 12,1944,seria1N0.5'5a,381

`si Claims. i w1. 12o-f4.7)

generally to fountain pens fountain pen My invention relates and has todo particularly with a provided with a multiple-stroke filling device ofthe type including a breather tube extending from the feed structure ofthe pen into the ink reservoir thereof. f

The principal object of my invention is to provide 'an improved fountainpen of the foregoing character.

Another object is to provide a fountain pen having provision forpreventing leaking and nooding, and particularly a fountain pen wellsuited for use in airplane travel.

A further object is to provide a fountain pen of the foregoing characterhaving provision for automatically preventing such change in the normalpressure relationship existing. between the air within and outside ofthe reservoir, when a reduction of atmospheric `pressure occurs, as'would cause iiooding or leaking of the pen.

Still another object is to provide a fountain pen of the foregoingcharacter wherein the length of the breather tube is such relative tothe volumetric i,

capacity of the ink reservoir that proper pressure conditions within thereservoir to prevent leaking or flooding are maintained.

l. A still further object is to provide a fountain pen of the `foregoingcharacter `wherein the breathertube is so located in the reservoir as toprovide for automatic re-establishment of the normal pressurerelationship existingbetween the air within and outside of thereservoir, upon reduction of atmospheric pressure.`

A more specific object is to provide a fountain pen of the foregoingcharacter wherein the breather tube has a free and open end projectinginto the ink reservoir and terminating interme-l the` reservoir short ofthe volu` thereof so that the end of the be open to the air inthereserdiate the ends of metric mid-plane breather tube will `voir in atleast horizontal and point-up positions of the pen.

A further object is to `providea fountain pen o f g the foregoingcharacter .which is so constructed andarranged that bedischargedJfromtheink' reservoir under the does not exwhich the feedmechanism is capable of retaining without leaking and flooding.

I Other objects and advantages will become apparent as the followingdescription progresses and by reference Figure 1y is a longitudinalsectional view on an enlarged scale, showing a fountain pen embodyingFOUNTAIN PEN Janesville, Wis., assignor to'Thef the amount. of ink' thatmay to the accompanying drawing, in`

the features of theinvention, with the pen in a vertical or fillingposition. l

Fig. 2fis a view showing the pen with its point end up as when carriedin the pocket. f .5 l Fig.-3 is a viewshowlngthe penfin `writingposition. l j l l l Fig. 4` shows the pen in horizontal position as whenlying on a desk orin a handbag. j l

The fountain penfwhich I have chosen to illustrate my inventioncomprises a barrel I0, the interior of which constitutes an inkreservoir. It

l front end of the barrel in communication with the v f In thebroaderfaspects of the l ink reservoir Il. inventionany suitable vfeed`structure capable of .use with a multiplestroke filling device may beemployed. However, the particular feed structure shown herein, and `inconnection with which my invention has special utility, vis ofthe typedis- 25 closed in ,United States `I etters Patent Non 2,223,541 grantedto Marlin S. Baker on December 43, 1940. Other forms of feed structurethat may be used are illustrated in ted States Letters 30 Patent Nos.1,980,508 grantedfgto Ivan D. Tefft on November 13, 1934,` and 1,904,358granted to ArthurQDahlberg on Aprils 18, 1933.

The feedstructure illustrated (Fig. ilincludes an ink governor orcollector device I3 mounted in the front end ofl the barrel IIIincommunication 35 with the ink reservoiri I. This governoris providedlwith a capillaryl ink feed passage Il inter- `secting a plurality'ofannular capillary` cells I5 adaptedto receive and store ink that may`tend 46 tofiowfro he reservoir II through the feed passage ,irri-excessof that required for writing purposes. The governor I3 receives andsupports a ,feedjrpar I6 and a tubular pen point I1, these ihffpartsbeing arranged to provide capillary passages IS connecting withthefeedgpassage I4 and i the writing tip I8 of the pen nib I1, as morefullyy 'described in said Baker Patent No. 2,223,541. The governor I3,`feed bar I6 and pen nib I'I, except the writing 'tip I8 of the latter,are enclosed within 50 a shell I9 secured to the forward end of the penbarrel by a bushing member 20. i In the use of the feed structure justdescribed, air is permitted to flow to the reservoir I I through `anopening!! in the forward end of `the shell 5 I9 and `thence through therearniost capillary `governor vcelll or cells I5, `when they'a're freeof ink, to bubble back to the ink reservoir through the rear end of theink passage I4. The admission of air to the reservoir in the normalwriting operation is necessary in order that ink may be withdrawn fromthe reservoir for writing purposes; but when, after a condition offlooding or leaking and the capillary governor cells I5 have inktherein, air cannot pass therethrough to the ink reservoir so thatfeeding of further ink from the reservoir is 'discontinued and ink istaken only from the governor structure in further writing until thegovernor cells are again clear.

A cap 22 is adapted to be detachably fitted to the front end of the penfor protecting the writing point thereof when the pen is not in use,which cap, if desired, is adapted to be iltted upon the rear of thebarrel when the pen is in use.

Referring to Fig. 1, a filling device, indicated generally at 23, of themultiple stroke type, such as shown in said Dahlberg Patent No.1,904,358, is secured at the rear end of the barrel I0. This fillingdevice includes a flexible diaphragm 24 actuated by a reciprocableplunger 25 to vary theeifective volume of the reservoir II to cause inkto be drawn thereinto in the manner fully explaned in said Dahlbergpatent. That is to say, on each complete stroke of the filling plunger25 a small quantity of ink is drawn into the reservoir so that thereservoir maybe filled to a predetermined extent upon the completion ofa plurality of strokes.

'I'he filling device 23 further includes a socalled breather tube 26which has one'end supported within an opening in the rear end of thefeed bar I6 in communication with the capillary ink passage I4 and itsother end extending rearwardly within and in communication with the inkreservoir. As taught by the Dahlberg patent, air is expelled through thebreather tube 26 in the operation of the filling plunger 25 and therelative displacement of air and ink upon actuation of the plunger 25 issuch as to cause the filling of the pen as above mentioned.

It will be appreciated that in the use of a lling device of the typeillustrated in Fig. 1, the filling of the reservoir may be continued bymultiple stroke action until the level of the ink in the. reservoirreaches the open end of the breather tube. Should the filling operationbe continued after this, ink may be drawn into the reservoir in anamount equal to that which is drawn into ,thev reservoir during onefilling stroke, thereby raising the level of the ink in the reservoir tothat thereof. To this end, in the last lling stroke, the front end ofthe pen may be lifted from the ink supply from which it is being lledand the filling plunger 25 released after such removal so that in thevery last suction stroke there is drawn into the ink reservoir ink in anamount not exceeding the capacity of the governor I3. Therefore, it willbe obvious that in the pen of the particular type shown, the ink levelwill not be extended beyond the end of the breather tube 26 to an extentin excess of the volume of ink that may be stored in the governor I3.

In pens of the type shown in said Teift and Dahlberg patents, Nos.1,980,508 and 1,904,358, respectively, the last filling stroke-may becompleted with the front end of the pen immersed in the'body of ink fromwhich the pen is being filled. In that case, upon complete filling, theamount of ink in the reservoir beyond the open end of the breather tubewill not exceed the volume of ink drawn into the reservoir on one normalfilling stroke of the pen.

In prior pens embodying the foregoing type of lling mechanism, thebreather tube has always been of such length as to extend in closeproximity to the rear end of the ink reservoir so as to enable thefilling of the reservoir substantially completely. This has presented aseriousdifficulty from the standpoint of leaking and flooding inairplane travel. For example, with the foregoing prior breather tubearrangement, when the pen point is in an inverted or upright position,as when carried in ones pocket, the open end of the breather tube iscompletely submerged in the ink in thereservoir and, during air travel,in the ascent of the plane the reduction in th'e outside -air may becomesuch that the pressure of the air in the reservoir acting on the inkextent above the open end of the breather tube.y l

If the filling Operation is continued after the latter condition exists,ink instead of air will be forced out by the filling device, upondepression of the filling plunger 25, so that regardless of additionalfilling strokes, substantially the same amount of ink will be forced outas is drawn in, no air being forced out because, under the conditionstated, the end of the tube is covered with ink, and air cannot beforced out until the ink level is reduced to uncover the end of thetube. Therefore, it will be seen that the extent to which the reservoirmay be filled, i. e., the maximum ink level in the reservoirisdeterminable by the length of the breather tube 26.

'I'he type of pen disclosed in the drawing isy well known in the tradeas the 51? pen` manufactured and sold byThe -Parker Pen Company ofJanesville, Wisconsin. In lling this pen it is desirable that thefilling operation be carried out in such a way that the governor I3 issubstantially cleared of ink upon the completion will cause ink to bedischarged from the reservoir through the breather tube and thecapillary passages connected therewith. In this case, the open end ofthe breather tube remains submerged until the reservoir is almost empty,and the amount of inkdischarged may be in excess of the capacity of thefeed mechanism to absorb the same so that excess ink leaks or floods atthe writing tip of the pen into the closure cap (corresponding to theclosure cap 22) which will then be in place on the front end of the pin.If this condition exists removal of the cap 22 for use of the pen in theairplane will result in smearing of ink upon ones hands and clothing. Myinvention completely avoids the foregoing objectionable' condition andprovides a pen in which ch'angesof pressure within the reservoirrelative to the outside atmosphere will not cause ink tobe forced fromthe pen to cause leaking or flooding at the writing tip ,5 I6 thereof inany position of the pen. Tdtheforegoing end the breather tube 26 ispositloned-.poncentrically in the reservoir II and is of such-lengthrelative to th'e volumetric capacity of-the reservoir Il that its openAend is at all times open to the air space in the reservoir in theinverted or point-up position of the pen.

Specifically, I attain the foregoing result by positioning the inner oropen end of the breather tube 26 at such apoint between the oppOsiteends i ofthe reservoir that the maximum level of the cated at 28 in Fig.2 when the pen is in point-up or inverted position. yMore particularly,the reservoir II is of such length and diameter that.

o a accuses 3 after the feed and filling mechanisms are assemwill bebelow the open end of the breather tube 4 bled as shown, the volumetricmid-plane thereof 1 26 inthe writing position ofthe pen, and theprop-'(a plane perpendiculargto the longitudinal axis e t erpressurecondition may be established through of the reservoiranddividingthe volumetric cathe breather tube withoutinkxbeingdischarged paclty ofthe reservoir into two equal parts) is lo-6 I into the governor or feed means. e v s, y cated on the line AiFigs.land 2).,andthe inner l I claim:` l .l eA, j end of the breather tube 26terminates lshort or 1. Aifountain'pen comprising areservoinafeedforwardly of the volumetric mid-planeby a disstructure, and a multiplestroke` filling devlceintance greater than on -halfthe longitudinaldicluding Aa breather tube extending `freinsaid feed mension in thereservoir of the'volume of ink that 10 structure intosaidreservoir, theinner endof said can be taken inon one suction stroke of the llbreathertube beingshort of the volumetric miding device. In this arrangementthevolume of i 1 planeof said reservoirby a distance greater than thereservoir II forwardly of the inner end of one halfthe'longitudinaldimension in the reserthe breather tube 26 is less than the vclume'rear--voir of the ink thatcan be `tfalfzeniri by onesuc-I wardly thereof. 'f15 tion stroke `ci! thenllingdevice whereby theellevel Y, When thepen isin its point-.11D Position (Fig. of the ink will be below the `ende of,the breather 2), the open end of' the breather tube 26 will tube whenthe penis positioned withthepolnt endalwayslieintheairspaceinthereservoirsothat up. .l L l I if there is anytendency to disturb the normal 1` 2. A fountain pen comprisingareservoinafeed pressure relationship between the air within andstructure secured tothe front end of the reservoir, outside of thereservoir, asin airplane travel. and a multiple stroke nlling devicemounted in which would otherwise causea dischargeofink Y' the rearend.of the reservoir and. including a from the reservoir, such pressurerelationship will breather tube extending from said feedlstructure beautomatically reestablished through' the into said reservoir, the rearendofsaidbreather breather tube, preventing discharge of ink from `tubebeing spaced. forwardlygof the volumetric the reservoir. midplane ofsaid reservoir bye, distancegreater t When using a completelyfilledpenin writing .than one half the longitudinaledimension` in thel position,the ink Awill assume a1 level such as in- 1 reservoir of the volume ofinkthat can betaken l `dicated at 32 in Fig. 3.] In thiscase the volumeini `on oneysuction stroke` of thefiiling`" device,

e of the ink above vthe open end of the breather 3o whereby the level ofthe inkwill be below the end tube is no greater thanthe capacity of thegovl of the breathertube when the pen isy positioned ernor I3.Therefore, if in this case, the normal withjthefront end up. 2 ipressure relationship is disturbed suiiiciently to -l 3. -Afountainpenhaving an ink reservoir, an-

cause discharge of ink from the reservoir,` I I, the s c ink feedconnectedwith said reservoir, and filling amount of ink discharged wouldnot exceed the 85 mechanism for said reservoircomprising `a dis-lcapacity of the governor I3 andit'wouldA be taken placement element,andan air. discharge :element up therein without flooding or leaking atthe writ` projecting from said `ink feed into the e reservoir ing pointof the pen. l only to apoint. where theink drawn in on the In thehorizontal position of the pen, as shown last suction stroke of thedisplacement element" in Fig. 4, the ink will assume a level, indicated40 will fill the reservoir to a level spaced above the at 33, which isonly slightly above the axis of the volumetric mldplane of the reservoira `distance breather tube 26 because the latter is concentric less thanone half the longitudinal dimension in with the reservoir. Thus, theinner end of the the reservoir of the ink that can be taken in by lbreather tube 26 will be located at least partially one suction strokeof the displacement element within the air space' in the reservoir.Since air 45 whereby said air discharge element extends into will passthrough the breather tube and feed the air space in the reservoir whenthe `pen is structure more easily than ink, a disturbance of positionedwith its front end up. the normal pressure relationship wilicause air,4. A fountain pen comprising a reservoir, ink rather than ink, to bedischarged from the resfeed means in the front end of the pen, fillingervoir. While tilting the pen so that the point 5 means in the rear endof the pen. and air disis down will tend to shift the ink level abovethe charge means in said ink feed means, said lling end of the breathertube, the ink above the end of means inc1uding a tubular elementconstantly in the breather tube will be forced from the reservoir ecommunication with `Said air diseharge means into the cells 2l),I aswhen the pen is in writing and opening into the reservoir at a pointbetween Position, and n0 leaking or flooding will Occur. 55 said inkfeed means and filling means and deter- Thus, in a pen construction inaccordance with mining the level towhich said filling means can myinvention, the rear end of the breather tube fill said reservoir, saidpointbeing so located that will be within the air space in the reservoirfor the volume of the reservoir f0rward1y of said point,` normalcarrying positions of the pen, and conis less thanthe volume of saidreservoir rearward-` sequently upon disturbance of the normal presly ofsaid level, whereby said element opens into n sure relationship, airalone will be forced out of the air space in the reservoir when thefrontend the reservoir through the feed structure. Should is up; n the pen becompletely filled and used for writing 5. A fountain pen comprising abarrel provid under such conditions, or carried with the point ing areservoir, a feed structure secured tothe w l `end, down, only 'so muchink as can be stored in 55 front end of the barrel, and amultiple-stroke the cells20 will be discharged from the barrel. llingdevice mounted in the rear end of the y Thus in no case will the pen becaused tov leak or barrel and includingV a breather tube 'extendingflood at the writing tip. The pen may therefore rearwardly inandconcentrically with said reserl be safely carried and used duringairplane travel. voir from said feed structure, the inner end of Theforegoing description takes a completely said breather tube beingspaced'forwardly from filled pen into consideration, which is themaxithe volumetric midplane of said reservoir by a mum condition thatcan be imposed. However, distance greater than one-half the longitudinale it will be appreciated that in many conditions of dimension of thevolume of ink that can be drawn -f use (which will be the case in themajority of into the reservoir by one suction stroke of the instances)the level o: the ink in the reservoir 7 mung device. i

inner end short of the volumetric midplane of the reservoir a distancegreater Athan one-half Vthe longitudinal dimension in the reservoir ofthe 4ink that can be taken in' by one suction stroke of' the fillingdevice whereby flooding or leakj ing 'of the penis prevented when thenormal pressurerelationship between air. within and outside of'thereservoirl is disturbed for any position ofthe pen.

7. A fountain pen-'comprising a'reservoir, a

feed structure having an ink passage from said reservoir and means forstoring excess ink opening directly ,into said ink passage, andl amultiple-stroke filling device including a breather tube voir forwardlyof said point is less thany the volume rearwardly therefrom by an amountgreater than the volume of ink that can be taken in on'one suctionstroke of the filling device, whereby leaking or flooding of the. pen ispre- "vented when the normal pressure relationship y between the airwithin and outside of the reservoir is disturbed for any position ofthepen. 8. A fountain pen comprising a reservoir, a feed structure havinganink passage and means said feed structure into said reservoir with its iy y extending from said feed structure into said resj 'ervoir to a pointwhere the volume of said reser- Y plane of thereservoir a` distancegreater than one-halfthe longitudinal dimension in the reservoir of theink that can be taken in by one suction strokeof the fillingdevice, theink in said excess ink storage means being withdrawn therefrom into thereservoir 'at the conclusion of the lling operation whereby any inkdischarged from the reservoir by a disturbanceof the normal pressurerelationship between the air within and outside of the reservoir, whenthe point end is down, will be taken up by said excess ink storagemeans.

9. A fountain pen lcomprising a reservoir, a feed structure at the frontend ofthe pen having an ink passage from said reservoir and capillaryink storage cells opening into said ink passage, anda multiple-strokefilling device at the rear endof the penv including a breather tubeextending rearwardly from lsaid feed structure into said reservoir andldetermining the level to which said filling device can ll saidreservoir, the inner end of said breather tube being so located that thevolume of the reservoir forwardly of said inner end is less than thevolume of said reservoir rearwardly 0f said level whereby the breathertube opens into the air space in the reservoir whenA theY front end ofthe pen is up, the Linl: entering said cells during filling being'withdrawn into the reservoir by a suction stroke of theV filling deviceat the conclusion for storing excess ink in direct communication withsaid reservoir, and a multiple-stroke fill- 4ing device including abreather tube extending of the filling operation whereby the maximumquantity of ink from thereservoir that will be discharged therefrom by adisturbance of the normal pressure relationship between the air withinand outside of the reservoir. when the point end is down .will be equalto the capacity of said cells and will be taken up thereby.

I DAVID F. MOI-DTS.

